The possibility to estimate the resulting DVOR bearing error caused by multiple WTs summating the known errors of the particular WTs is investigated. The linear addition is found to be not suitable for use as a worst case estimation. Good estimations are achieved by the geometrical addition in proximal operation distances. In general bearing errors are decreasing with rising distance of WT and analysis point from DVOR. So the estimations can be interpreted as a kind of worst case values.

To investigate the possible interference of wind turbines with terrestrial navigation aids and Radar systems, the signals of these systems have to measured in the air space used by aircrafts or being under surveillance, respectively. From the measurements performed in areas with and without wind turbines the influence of these on the signals of terrestrial navigation and/or Radars can be derived. Drone-based and state-of-the-art electronics were used for the measurements.